import logging

USER_AGENT = 'YCast'


class Directory:
    def __init__(self, name, item_count):
        self.name = name
        self.item_count = item_count


def generate_stationid_with_prefix(uid, prefix):
    if not prefix or len(prefix) != 2:
        logging.error("Invalid station prefix length (must be 2)")
        return None
    if not uid:
        logging.error("Missing station id for full station id generation")
        return None
    return str(prefix) + '_' + str(uid)


def get_stationid_prefix(uid):
    if len(uid) < 4:
        logging.error("Could not extract stationid (Invalid station id length)")
        return None
    return uid[:2]


def get_stationid_without_prefix(uid):
    if len(uid) < 4:
        logging.error("Could not extract stationid (Invalid station id length)")
        return None
    return uid[3:]